This invention relates to new polymerization catalysts, a process for preparing the catalysts, and use of the catalysts for the homopolymerization and copolymerization of olefins. In another aspect, this invention relates to a catalyst prepared by halogenating magnesium oxide, followed by treatment with an alcohol and a titanium tetrahalide. In another aspect, this invention relates to the formation of a catalyst as defined above which can be used with a cocatalyst comprising a metallic hydride or an organometallic compound to form a catalyst system useful for the polymerization of alpha-olefins. In a further aspect, this invention relates to a process for polymerizing alpha-olefins using a catalyst system wherein a first catalyst component is prepared by halogenating magnesium oxide, then treating the halogenated product with an alcohol and a titanium tetrahalide.
It is known to polymerize alpha-olefins and mixtures thereof in a low pressure process wherein organometal catalysts used are prepared from mixtures of compounds of elements of Subgroups IV-VI of the Mendeleev Periodic Table and the organometallic compounds of the elements of Groups I-III of the Periodic Table. The polymerization is generally carried out in suspension, in solution, or even in a gaseous phase.
The activity of an olefin polymerization catalyst is one important factor in the continuous search for a catalyst useful for the polymerization of alpha-olefins. It is also desirable that the process used in forming the catalyst be such as to allow ease in preparation and to allow control over the final catalyst formed. It is also desirable to produce titanium-based catalysts that comprise chiefly an inert support, which is not harmful when left in the polymer. It is also advantageous to prepare a polymer containing low amounts of residual catalyst materials whereby deashing of the produced polymer can be eliminated and a simple deactivation of the residual catalyst is all that is required. The present invention relates to an improved catalyst exhibiting increased activity and possessing some of the above-mentioned advantages.
Accordingly, an object of this invention is to provide an improved polymerization catalyst.
Another object of this invention is to provide a process for preparing a novel catalyst.
Another object of this invention is to provide an improved process for the polymerization of alpha-olefins.
Other objects, aspects, and the several advantages of this invention will be apparent to those skilled in the art upon a study of this disclosure and the appended claims.